Deposition and Electrical Resistivity of Oxygen-Deficient Tin Oxide Films Prepared by RF Magnetron Sputtering at Different Powers

A series of oxygen-deficient tin oxide thin films were deposited by radio frequency magnetron sputtering a sintered tin oxide ceramic target under pure argon atmosphere at different sputtering powers (80-160 w) under the based pressure of no more than 2.0×10-4 Pa, sputtering pressure of 2.0 Pa and deposition time of 20 min. It was revealed that all the as-deposited films were oxygen-deficient tin oxide films, and the main defect in films was oxygen vacancy (VO), whose concentration gradually decreased with the increase of sputtering power. The films prepared at a power of no more than 120 w were amorphous, and as the sputtering power increased to 140 and 160 w, the deposited thin films exhibited polycrystalline characteristics with (110), (101) and (211) diffraction peaks of tin oxide. The grain size, deposition rate as well as thickness of the obtained films rose up with increasing sputtering power. In addition, as the sputtering power raised, the electrical resistivity of the films increased, due to the electron conducting mechanism controlled by VO in the samples.